Method and apparatus for carrying out doffing and donning operation

ABSTRACT

An improved method and apparatus for carrying out the doffing and donning operation of a spinning machine such as an open-end spinning machine. A suction nozzle is carried along the lengthwise direction of the spinning machine at a position before and above the take-up mechanisms of the spinning machine at the time of carrying out the doffing and donning operation. The suction nozzle is capable of holding a leading end portion of a yarn delivered from each spinning unit and this leading end portion of the yarn is caught by a fresh bobbin before the bobbin is mounted on a cradle of the take-up mechanism from outside the spinning machine and, then, the bobbin is mounted on the cradle and the take-up operation is commenced. The suction nozzle is capable of being stopped at any position along the passage thereof by manual operation.

SUMMARY OF THE INVENTION

The present invention relates to an improved method and apparatus forcarrying out the doffing and donning operation of a spinning machine,such as an open-end spinning machine.

It is well known that, in the spinning operation wherein an open-endspinning machine is utilized, when the size of yarn packages formed bythe respective taking up mechanisms attains a predetermined full size,such full size yarn packages are doffed from the respective taking-upmechanisms while the yarn extending between the full yarn package andthe delivery part of the spinning unit is severed at a portion adjacentto the yarn package of each spinning unit. Thereafter, a leading and ofthe yarn from the spinning unit is held by a corresponding suction meansand, next, the leading and of delivery yarn is manually or mechanicallycaught by a fresh bobbin. Thereafter, the fresh bobbin is positioned ona cradle of each taking up mechanism so as to start the formation of anew yarn package about the fresh bobbin. According to our experience inmill operations, the above-mentioned method for doffing and donning fullsize packages from the respective take-up mechanisms involves severaldrawbacks. That is, for example, it is necessary to utilize a suctionmeans for each spinning unit so as to hold a leading end of yarndelivered from the corresponding spinning unit. Therefore, the cost foradopting these suction means is high because of the high installationcost. Further, these suction means need a large amount of suction airfor carrying out the doffing and donning operation. Moreover, sincethere are provided numerous overhead suction means disposed along thelengthwise direction of the open-end spinning machine at the positionabove an alignment of the take-up means, these suction means make itdifficult to provide good lighting for the take-up mechanism.

The principal object of the present invention is to provide an improvedmethod and apparatus for carrying out the doffing and donning operationof a spinning machine, particularly an open-end spinning machine.

In the improved method of the present invention for carrying out thedoffing and donning operation of a spinning machine, a suction means forholding a leading end of yarn delivered from a spinning unit isdisplaced along the longitudinal direction of the spinning machine and asuction nozzle extends to a position right above the floor of thespinning mill. In this embodiment of the present invention, a mainsuction duct is disposed along the longitudinal direction of thespinning machine at a position above the spinning machine and a movablesuction nozzle is displaceably connected to the main suction duct sothat the suction nozzle is capable of displacing along the longitudinaldirection of the spinning machine when the doffing and donning operationof the spinning machine is carried out. In a modified apparatus of thepresent invention, the above-mentioned suction nozzle is capable ofstopping at any position along the longitudinal direction of thespinning machine. Therefore, the above-mentioned drawbacks of theconventional suction means utilized for carrying out the doffing anddonning operation of the spinning machine can be eliminated perfectlyaccording to to the present invention.

BRIEF EXPLANATION OF THE DRAWINGS

FIGS. 1A, 1B, 1C and 1D are schematic side views of a conventionaldoffing and donning apparatus, showing steps of a doffing and donningoperation.

FIGS. 2A, 2B, 2C and 2D are schematic side views of an improvedapparatus for carrying out the doffing and donning operation, showingsteps of a doffing and donning operation, according to the presentinvention.

FIG. 3 is a schematic front view of an open-end spinning machineequipped with a suction means utilized for the doffing and donningapparatus according to the present invention.

FIG. 4 is a side view of the suction means, and related parts of thedoffing and donning apparatus shown in FIG. 3.

FIG. 5 is a plan view of a belt utilized for the suction means shown inFIG. 4.

FIG. 6 is a schematic side view of a modified engaging means of thesuction means shown in FIG. 4.

FIG. 7 is an explanatory plan view of a modified suction means accordingto the present invention.

FIG. 8 is a schematic front view of an open-end spinning machineequipped with the modified suction means shown in FIG. 7.

DETAILED EXPLANATION OF THE INVENTION

For the sake of easy understanding of the characteristic feature of thepresent invention, the doffing and donning operation carried out by aconventional apparatus, which was disclosed in a copending patentapplication, Ser. No. 460,086, filed on Apr. 11, 1974, now Pat. No.3,940,076 is firstly explained.

Referring to FIGS. 1A, 1B, 1C and 1D, wherein steps of the doffing anddonning operations of the above-mentioned conventional apparatus areshown, a sliver 3 contained in a can 2 is supplied to an open-endspinning unit 1 and a yarn 10 is delivered from the spinning unit 1 bymeans of a take-up force created by delivery rollers 4 and 5, whereinthe roller 4 is positively driven by a driving mechanism (not shown)while the roller 5 rotatably contacts the roller 4. Then the yarn 10 iswound on a bobbin 8 by a take-up mechanism comprising a friction roller6 and a bobbin holding cradle 7 which is turnably mounted on a pivotshaft 7a in such a condition that the bobbin 8 is capable of contactingthe friction roller 6. In this take-up mechanism, the friction roller 6is a split drum which is positively driven by a driving mechanism (notshown) and provided with a yarn guide groove for traversing the yarnpassage along the longitudinal axis of the bobbin. The size of a yarnpackage formed on the bobbin 8 is increased, until a full yarn package 9is formed, by take-up of the yarn 10 according to the rotation of theyarn package formed on the bobbin 8. This rotation is created by thefrictional contact of the yarn package with the split drum 6. Then, thefull yarn package 9 is doffed from the above-mentioned winding mechanismand displaced to a conveyer belt 18 disposed along the lengthwisedirection of the open-end spinning machine at a position adjacent to thewinding mechanisms of the spinning machine.

Since the construction of the cradle 7 is disclosed in theabove-mentioned copending application, the detailed explanation thereofis omitted. The cradle 7 is capable of turning upward from the splitdrum 6. A suction duct 25 is disposed above the take-up mechanism and asuction nozzle 26 connected to the suction duct 25 is disposed at theupper position of the cradle 7 right above each take-up mechanism.Consequently, after doffing a full yarn package 9 from the bobbincatchers (not shown) of the cradle 7, when the yarn 10 carried from thedelivery rollers 4 and 5 is sucked into the suction nozzle 26, the yarnpasses beyond the surface of the split drum 6 on the side where the yarnpackage contacts the split drum 6. A bobbin holder 27 is mounted to thebottom outside of the suction nozzle 26 so as to detachably hold thefresh bobbin 8a in such a condition, that, when the bobbin holdingcradle 7 is turned toward the suction nozzle 26, the bobbin holdingmeans (not shown) mounted on the cradle 7 arrives at the position of thebobbin holder 27 and a fresh bobbin 8a is transferred from the bobbinholder 27 to the bobbin holding means of the cradle 7 automatically.

After this the fresh bobbin 8a is taken from the bobbin holder 27 by theturning of the cradle 7 toward the split drum 6. In this embodiment, itis further essential to dispose the bobbin holder 27 at a position onthe suction nozzle 26 which is opposite the side just above the yarnpassage over the split drum 6 and the conveyer 18 (FIGS. 1A through 1D)when the yarn end is sucked into the suction nozzle 26, A guide plate 17is disposed between the split drum 6 and the conveyer 18 so as to guidea full yarn package 9 to the conveyer 18.

A fresh bobbin 8a is inserted into each bobbin holder 27 of eachspinning unit, before commencing the doffing operation as shown in FIG.1A. When a full yarn package 9 has been formed on a bobbin 8, thedoffing operation is commenced. An operator cuts the yarn 10 at aposition between the delivery rollers 4, 5 and the take-up roller 6. Theabove-mentioned cutting operation is carried out manually or by using asuitable cutting apparatus. The yarn portion connected to the yarnpackage 9 is wound around the yarn package 9 and, if the above-mentionedoperation is carried out manually, the end of the yarn connected to theyarn delivered from the delivery rollers 4 and 5 is held in the hand ofthe operator. Then after doffing the full yarn package 9 from the cradle7, the cradle 7 is turned toward the suction nozzle 25 manually. (FIG.1B)

During the above-mentioned upward turning motion of the cradle 7, thefull yarn package 9 rolls along a slope formed on the guide plate 17toward the conveyer belt 18 and rests on the conveyer belt 18, and asthe yarn 10 is continuously being delivered from the delivery rollers 4and 5, the delivered yarn is carried to the suction nozzle 26 so as tobe continuously sucked thereinto. (FIG. 1B)

When the cradle 7 is turned to the terminal position of its upwardturning motion, the bobbin catchers (not shown) of the cradle 7 hold afresh bobbin 8a, which is also being held by the bobbin holder 27 asalready illustrated, while the yarn continuously being delivered fromthe delivery rollers 4 and 5 is continuously sucked into the suctionnozzle 25 from a yarn passage passing before the take-up roller 6.

In the above-mentioned condition, the conveyer belt 18 carries the fullyarn package 9 outside the open-end spinning machine. After that theyarn is urged against the split drum 6 by the downward turning motion ofthe fresh bobbin 8a, which is turnably held by the bobbin catchers (notshown) of the cradle 7, and nipped by the fresh bobbin 8a and the splitdrum 6. (FIG. 1C)

Next, when the yarn 10 between the suction nozzle 26 and the freshbobbin 8a is cut manually or by a suitable cutting device (not shown)into two portions, wherein an upper portion is extending from thesuction nozzle 26, while the other portion is extending from the freshbobbin 8a. And the upper yarn portion of the yarn is sucked into thesuction nozzle 26, while the other portion of the yarn falls on thefresh bobbin 8a so that this yarn portion is wound on the bobbin 8a dueto the rotation of the bobbin 8a. (FIG. 1D) As the yarn portion is woundon the fresh bobbin 8a is mentioned above, the winding operation on thebobbin 8a can be commenced.

The above-mentioned method and apparatus for carrying out the doffingand donning operation of an open-end spinning machine involves problemswhich need to be solved, as pointed in the above Summary of theInvention. Therefore, in the apparatus according to the presentinvention, particular effort has been directed to elimination of theabove-mentioned drawbacks of the conventional apparatus mentioned above.

Referring to FIGS. 2A, 2B, 2C, 2D, 3 and 4, in the apparatus accordingto the present invention, a suction duct 11 is disposed along alongitudinal direction of a spinning machine A at a position above anAligned raw of take-up mechanisms of spinning units, and the suctionduct 11 is connected to a suction blower 19 (FIG. 3) mounted on a gearand frame B. The suction duct 11 is provided with a horizontal aperture(not shown) extending along the lengthwise direction of the spinningmachine A and covered with a flexible plate 11a. A suction nozzle 12 isdisplaceably engaged into the horizontal aperture in such a way that theflexible plate 11a allows displacements of a connecting pipe 12a of thesuction nozzle 12, but always closes the remaining portion of thehorizontal aperture beside the engaging part of the aperture with theportion 12a. Consequently, air is sucked into the suction nozzle 12 froma mouth thereof after being sucked through the suction duct 11, due tothe engagement of the horizontal aperture with the connecting pipe 12aof the suction nozzle 12. The detailed construction and function of theabove-mentioned suction means comprising the suction duct 11 and thesuction nozzle 12 is disclosed in detail in the copending patentapplication Ser. No. 460,086 filed on Apr. 11, 1974. However, the gistof the construction and function of the above-mentioned suction meansutilized for the apparatus of the present invention is hereinafterillustrated.

The suction nozzle 12 is mounted on a carrier member 13 provided withrollers 14 which are capable of running along the corresponding railsmounted on the suction duct 11 as shown in FIG. 4. The carrier member 13is displaced by a driving means comprising a driving pulley 20, which isdriven by a motor (not shown), and an endless belt 15 which is disposedalong the passage of the carrier member 13 and turnably held by thedriving pulley 20 and a guide pulley (not shown in FIG. 3) mounted on anoutend frame (not shown) of the spinning machine A. In the modifiedembodiment of the apparatus according to the present invention in FIGS.7 and 8, the above-mentioned driving means is modified in such a waythat the driving pulley 20 and the guide pulley 20a are secured to thecorresponding vertical shafts 28, 28a, respectively. The vertical shaft28 is driven by a motor (not shown) while the vertical shaft 28a isturnably mounted on the outer frame Ba as shown in FIG. 7. In thisembodiment the endless belt 15 is disposed above the suction duct 11.

In the two embodiments shown in FIGS. 3 and 4, FIGS. 7 and 8 the duct 11is provided with a longitudinal horizontal aperture formed in the topwall of the duct 11 along the length of the machine and a suction nozzle12 for holding a yarn end in the doffing and donning operation ismounted by way of a connecting pipe 12a on the carrier member 13 whichtravels along the machine frame. The connecting pipe 12a connected tothe suction nozzle 12 is inserted into the duct 11 through a spacebetween the skirt portion of the flexible covering plate 11a and an edgeof the aperture of the duct 11 as shown in FIG. 4. Therefore, theconnecting pipe 12a is connected to the duct 11 in a displaceablecondition. The connecting pipe 12a is rigidly mounted on the carriermember 13 by a bracket 13a. The end portion of the pipe 12a is expandedso that the transverse cross section of the duct 11 is occupied by theend portion of the pipe 12a. Therefore, the suction force created by thesuction blower 19 is effectively transmitted to the connecting pipe 12a.

Referring to FIGS. 4 and 5, the carrier member 13 is detachably engagedwith the endless belt 15 by way of an engaging member 16, so that thecarrier member 13 holding the suction nozzle 12 is capable ofdisplacement along the machine and can stop temporarily in front of atake-up mechanism of any spinning unit. The engaging member 16 isprovided with a pin 16a for engaging the carrier member 13 with the belt15. The belt 15 is provided with a plurality of apertures 15a, any oneof which is capable of accepting the pin 16a. The pin 16a is alwaysurged toward the belt 15 by an expansion spring 16b in order to maintainthe engagement of the carrier member 13 with the belt 15; however, if itis necessary to stop the carrier member 13 at a position in front of anygiven take-up mechanism of a spinning unit, the engagement of the pin16a with the belt 15 can be released by a manual control meanscomprising a guide member 24 and an operation handle 21 mountedrespectively on each suction nozzle 12, and an operation wire 22 whichconnects a top end portion 23 of the pin 16a and the operation handle 21by way of the guide member 24. In other words, when the wire 22 ispulled by the operation handle 21, the pin 16a is pulled from the belt15, releasing the engagement of the pin 16a with the aperture 15 a ofthe belt 15. In the above-mentioned embodiment, a safety device (notshown) which prevents simultaneous actuation of the engaging member 16by both operation handles 21, is mounted on the carrier member 13.

Another embodiment of the engaging member 16 is shown in FIG. 6. In thisembodiment, the engaging member 16 comprises an L shaped pin 16aturnably mounted on the carrier member 13 (not indicated in FIG. 6) by apin 16c. A handle 16d is rigidly connected to a free end of the L shapedpin 16 so as to turn the pin 16 about the pin 16c for engaging ordisengaging the pin 16 into or from the aperture 15a of the belt 15. Ahelical spring 16e is mounted on the carrier member 13 in such a waythat the L shaped pin 16a is always pulled so as to maintain theengagement into the aperture 15a of the belt 15, as shown in FIG. 6. Astopper 16f mounted to the carrier member 13 prevents any excessinsertion of the pin 16a into the aperture 15a of the belt 15.

Next, the operation of the above-mentioned apparatus shown in FIGS. 3and 4 is hereinafter explained. The carrier member 13 and the suctionnozzle 12 are reserved at a position outside the spinning unit 1, asindicated by a dash-dot line in FIG. 3. During the normal spinningoperation, the suction blower 19 and a motor for driving the drivingpulley 20 are also stopped. When the size of yarn packages formed by therespective take-up mechanisms become the predetermined full size, asshown in FIG. 2A an electrical means (not shown) for actuating thesuction blower 19 and the motor for driving the driving pulley 20 areactuated manually or by a signal issued from an automatic counter (notshown). An operator for carrying out the doffing and donning operationcuts the yarn between each full size yarn package on each take-upmechanism and the corresponding spinning unit 1 and carries a leadingend of the yarn delivered from the spinning unit 1 to the mouth of thesuction nozzle 12 so that the leading end of the yarn is sucked into thesuction nozzle 12. When the cut end portion of the yarn is wound on theyarn package 9, the cradle 7 is turned toward the suction nozzle 12,while the full size yarn package 9 is doffed from the cradle 7 anddisplaced to the conveyer belt 18 (FIG. 2B).

Next, the yarn held by the suction nozzle 12 is engaged by a freshbobbin 8 mounted on the cradle 7 and then the cradle 7 is turned towardthe split drum 6 so as to contact the bobbin 8 thereto. (FIG. 2C). Theabove-mentioned donning operation is carried out manually.

Then, the yarn extending from the fresh bobbin 8 to the suction nozzle12 is severed and, therefore, the cut end portion of the yarn which isseparated from the yarn held by the suction nozzle 12 is wound on thefresh bobbin 8. According to the above-mentioned operation, the cutportion of the yarn held by the suction nozzle 12 is sucked into thenozzle 12 and carried to a terminal of the suction duct 11, where it andother similar portions are accumulated as waste. In this condition, thenormal take-up operation of yarn 10 by the take-up mechanism iscommenced. (FIG. 2D).

In the above-mentioned embodiments of the apparatus according to thepresent invention, the driving speed of the endless belt 15 is selectedso as to displace the carrying member 13 a unit distance of one spinningunit 1 during the time required to carry out the doffing and donningoperation for a spinning unit 1. This driving speed may be changed so asto fit the skill of the operator. Since the above-mentioned time forcarrying out the doffing and donning operation is independent of thedelivery speed of the spinning unit, the operation can be carried out inthe best condition for the operator. In addition, if unexpected troublesoccur, the carrying member 13 can be stopped by easy manual operation ofthe operation handle 21 (FIG. 4) or 16d (FIG. 6).

Since the carrying passage of the mouth of the suction nozzle 12 isoutside the spinning unit with respect to the take-up mechanism, themounting operation of the fresh bobbin 8 on the cradle 7 can be easilycarried out as mentioned above. (FIG. 2C). To carry out the donningoperation more easily than in the above-mentioned embodiment, anautomatic yarn cutter, and/or yarn guide means may be utilized with theapparatus according to the present invention. Further, theabove-mentioned suction blower 19 may be mounted on the carrying member13 instead of utilizing the suction blower 19 stationarily disposed to agear end frame of the spinning machine and the suction duct 11.

What is claimed is:
 1. In an apparatus for carrying out doffing anddonning operations at each unit of a spinning machine, means forcontinuously delivering a yarn from said spinning unit, and a take-upmechanism provided with a friction roller and a cradle for rotatablysupporting a fresh bobbin or a yarn package formed on said bobbin incontacting relationship with said friction roller, said cradle beingpivotally supported on a shaft mounted on a bracket secured to a frameof said units, means for releasably and rotatably holding a bobbin onsaid cradle, said holding means being disposed on said cradle, suctionmeans disposed at a position on the opposite side of said delivery meanswith respect to said friction roller for temporarily forming a yarnpassage by a yarn continuously being delivered from said delivery meansat a position in front of the part of the peripheral surface of saidfriction roller where said yarn passes over during a normal taking upoperation, the improvement comprising means for displacing said suctionmeans in a direction lengthwise of said spinning machine to a positionoutside and above said take-up mechanism of each spinning unit at thetime of doffing and donning operations, and means for creating suctionforce in said suction means, said displacing means comprising means fortemporarily stopping said suction means at any point lengthwise of saidspinning units, said suction means comprising a suction nozzle providedwith a mouth opened at a position outside and above any of said take-upmechanisms and a connecting pipe connected to said suction forcecreating means, said suction force creating means comprising a suctionblower disposed at a gear end frame or an outer frame of said spinningmachine and a horizontal suction duct extending in a lengthwisedirection of said spinning machine at a position above said take-upmechanisms, said suction duct being connected to said suction blower andhaving an elongated aperture extending in the lengthwise direction ofsaid machine and covered with a flexible plate, said connecting pipe ofsaid suction nozzle displaceably extending into said duct through saidaperture, in a condition such that said flexible cover plate seals saidaperture of said suction duct other than at the portion of said aperturethrough which said connecting pipe of said suction nozzle extends, saiddisplacing means comprising an endless belt extending lengthwise of saidspinning machine at a position above said take-up mechanisms, anddriving pulley and a guide pulley respectively disposed at the endframes of said spinning machine, and a motor for driving said drivingpulley, said endless belt being held by said pulleys, a guide rail meansdisposed along said suction duct, a carrying member displaceably mountedon said guide rail, and an engaging member for detachably engaging saidendless belt with said carrying member, said connecting pipe being heldby said carrying member for movement lengthwise of said machine.
 2. Animproved apparatus for carrying out the doffing and donning operationaccording to claim 1, further comprising an actuating means forselectively engaging and disengaging said engaging member with saidendless belt, said actuating means being provided with a manuallyoperable handle.
 3. The apparatus of claim 2 wherein said manuallyoperable handle is mounted on said suction means, said actuating meansfurther comprising wire means extending between said manually operablehandle and said engaging member.